As Collins guides a surrogate through a difficult delivery, Robby does his best to keep a developing staffing situation under wraps. Meanwhile, McKay confronts her ex's overstepping girlfriend, and Whitaker watches Samira sniff out a drug-seeking patient.

As the night shift begins and the death toll rises, Robby refuses to give up on a mass casualty victim – even after Abbott intervenes. Unable to find an attending, Santos and Samira each attempt risky moves to save their patients' lives.